Serpent was selected as one of the 5 AES finalists

Serpent-1, the variant submitted to the AES is slightly different, and
is described here.

Serpent is now completely in the public domain, and we impose no
restrictions on its use. This was announced on the 21st August 1998 at the
AES conference. The OPTIMIZED implementations in the above submission
package are now under GNU PUBLIC LICENSE (GPL), although the comments
in the code still say otherwise. You are welcome to use Serpent for
any application. However, if you do use it, we would appreciate it if
you would let us know!